I am on BIS through T-mobile using a 8310. I have two accounts set up on my BB, one the push account with @tmo.blackberry... and the other a POP account. When I go to compose an email it has the POP account as the "send using default" and I keep forgetting to change it and wind up sending freshly composed emails from the wrong account (the POP account). I want the tmo.blackberry account to be the default. How do I switch this?

I'm sure it is something incredibly simple, but I've spent a while now trying to figure it out and I'm baffled.